/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package javax.servlet.jsp;

import javax.servlet.Servlet;

/**
 * The JspPage interface describes the generic interaction that a JSP Page
 * Implementation class must satisfy; pages that use the HTTP protocol are
 * described by the HttpJspPage interface.
 * 
 * <p>
 * <B>Two plus One Methods</B>
 * <p>
 * The interface defines a protocol with 3 methods; only two of them: jspInit()
 * and jspDestroy() are part of this interface as the signature of the third
 * method: _jspService() depends on the specific protocol used and cannot be
 * expressed in a generic way in Java.
 * <p>
 * A class implementing this interface is responsible for invoking the above
 * methods at the appropriate time based on the corresponding Servlet-based
 * method invocations.
 * <p>
 * The jspInit() and jspDestroy() methods can be defined by a JSP author, but
 * the _jspService() method is defined automatically by the JSP processor based
 * on the contents of the JSP page.
 * 
 * <p>
 * <B>_jspService()</B>
 * <p>
 * The _jspService()method corresponds to the body of the JSP page. This method
 * is defined automatically by the JSP container and should never be defined by
 * the JSP page author.
 * <p>
 * If a superclass is specified using the extends attribute, that superclass may
 * choose to perform some actions in its service() method before or after
 * calling the _jspService() method. See using the extends attribute in the
 * JSP_Engine chapter of the JSP specification.
 * <p>
 * The specific signature depends on the protocol supported by the JSP page.
 * 
 * <pre>
 * public void _jspService(
 * <em>
 * ServletRequestSubtype
 * </em>
 *  request,
 * <em>
 * ServletResponseSubtype
 * </em>
 *  response)
 *        throws ServletException, IOException;
 * </pre>
 */

public interface JspPage extends Servlet {

	/**
	 * The jspInit() method is invoked when the JSP page is initialized. It is
	 * the responsibility of the JSP implementation (and of the class mentioned
	 * by the extends attribute, if present) that at this point invocations to
	 * the getServletConfig() method will return the desired value.
	 * 
	 * A JSP page can override this method by including a definition for it in a
	 * declaration element.
	 * 
	 * A JSP page should redefine the init() method from Servlet.
	 */
	public void jspInit();

	/**
	 * The jspDestroy() method is invoked when the JSP page is about to be
	 * destroyed.
	 * 
	 * A JSP page can override this method by including a definition for it in a
	 * declaration element.
	 * 
	 * A JSP page should redefine the destroy() method from Servlet.
	 */
	public void jspDestroy();

}
